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Are you Carl Erdmann, author of the books below?
The Origin of the Idea of Crusade by Carl Erdmann Die Entstehung des Kreuzzugsgedankens by Carl Erdmann Studien zur Briefliteratur Deutschlands im elften Jahrhundert by Carl Erdmann Ottonische Studien by Carl Erdmann A ideia de cruzada em Portugal by Carl Erdmann Das Papsttum Und Portugal Im Ersten Jahrhundert Der Portugies... by Carl Erdmann O Papado e Portugal no primeiro século da história portuguesa by Carl Erdmann The Origin of the Idea of Crusade by Carl Erdmann The Origin of the Idea of Crusade by Carl Erdmann Papsturkunden in Portugal (Raabe,samtliche Werke) by Carl Erdmann


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